Ellipse.
He discovered that avery planet has a ellipcial orbit, which means oval.
Each planet is in its own orbit and obey's Kepler's laws of planetary motion. Newton later discovered that the Sun's gravity is what makes the planets move in their orbits in the way they do.
Kepler
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Johannes Kepler discovered that the Earth revolves/orbits the Sun in an ELLIPSE. He also discovered that the Sun is NOT at the centre of the ellipse, but at one of the foci ; (plural of focus). The other focal point being 'blind'. From this we have the definition, that as the Earth orbits the Sun , 'It sweeps equal arcs in equal times'. As the Earth orbits, it speeds up and slows down. It is moving at its fastest when passing the Sun at it nearest point ( perigee) and slowest when at its furthest point ( apogee). Have a look in Wikipedia under' Johannes Kepler.
It was Johannes Kepler in 1618.
Johannes Kepler discovered that planets orbit the Sun in ellipses with varying eccentricities in the early 17th century. This became known as Kepler's first law of planetary motion and revolutionized our understanding of planetary orbits.
Johannes Kepler formulated the laws of planetary motion in the early 17th century, including the discovery that planets move in elliptical orbits with the sun at one of the foci.
The orbit of each planet it the path it takes as it rotates round the Sun under the influence of the force of gravity. Every planet has a separate orbit and the orbits all follow Kepler's three laws of planetary motion.
Kepler's 1st law of planetary motion state that Each planet moves in an elliptical orbit with the sun at one focus.
The orbit of each planet it the path it takes as it rotates round the Sun under the influence of the force of gravity. Every planet has a separate orbit and the orbits all follow Kepler's three laws of planetary motion.
This particular innovation was made by Johannes Kepler, which resulted in the observations of the planets finally falling precisely into the calculations that were made with the heliocentric theory.